gach

Gach is the Vietnamese term for bricks and brick-like masonry units used in building and construction. It typically refers to fired clay bricks (gach nung) that form walls, partitions, and sometimes decorative facades, as well as bricks designed for paving and interior or exterior finishing. The broad concept also covers various ceramic or cement-based bricks produced for different structural and aesthetic applications.

Manufacture and materials are central to gach. Most traditional bricks are made from clay or shale, which is prepared, shaped in molds or by extrusion, dried, and then fired in a kiln to develop strength and durability. Modern brick production can also include fly ash or other supplementary materials and may use dry-press or autoclave processes for specialized products. The firing temperature, material composition, and manufacturing method influence brick color, density, water absorption, and compressive strength.

Common types include solid and hollow clay bricks, which differ in weight and insulating properties; facing bricks, chosen for appearance and texture on visible surfaces; and specialized bricks for paving or decorative effects. In some markets, gach can also be used to describe concrete blocks or other masonry units, though these are often categorized separately as blocks.

Properties and standards of gach vary by region and product. Typical considerations include compressive strength, durability, moisture absorption, dimensional tolerance, and thermal performance. Bricks are valued for longevity, fire resistance, and sound insulation, but performance depends on proper specification, quality control, and suitable construction practices.

Historically, bricks have been produced for thousands of years across many cultures. In Vietnam and neighboring regions, gach has long been a fundamental building material, with ongoing development toward improved strength, efficiency, and decorative versatility.